The invention applies to an arcwelding or cutting torch, like a WIG or plasma torch, with an electrode fastened in an electrode holder, which in turn is incorporated in a housing within the torch body.
An essential component of arcwelding or cutting torches is the electrode holder, which conducts the current for generating the arc to the electrode. The electrode holder is located in a housing within the torch body, while the electrode is fastened in the electrode C) holder. To accommodate electrodes of various diameters, an exchangeable electrode holder is used with the same outer diameter, but different inside diameters. The electrode holders contain expansion slits and a tapered part, with which they are pressed on the electrode. In the case of a WIG torch, a torch cap is screwed to the end of the torch body, which fastens the electrode within the adapter sleeve. With familiar torches, however, the centering of the electrode is difficult, because, as in the case with WIG torches, it has to be sighted in manually by the user, who simultaneously screws the torch cap on the torch body. So it can happen, that the electrode is not centered in the gas flow and can create detrimental flow conditions around the electrode. This causes the electrode to oxidize and to be consumed quicker by lower gas cooling or by forming turbulences with air intake.
These mechanical construction problems with familiar arcwelding or cutting torches can also lead to intermittent current conduction from the torch body or the torch housing to the electrode holder and from there to the electrode. For instance, this can cause different conditions during conduct of current after exchanging an electrode holder with the same inside diameter in a WIG torch, even after repointing and refastening the electrode. Sometimes this generates excessive transfer resistance between the electrode holder and the electrode and, consequently, high localized thermal loads on the electrode holder and unwanted heat transfer to the torch body and sometimes from there to the torch cap with the plastic covering.